Power converters typically require error circuitry that provides an “error” signal between the output voltage of the power converter and a reference voltage, in order to regulate the output voltage to a value compatible with the power converter. The error circuitry should provide a magnitude and a sign (positive or negative) of the output voltage, so that the power converter can use such error signal to properly regulate the output voltage against the reference voltage by increasing or decreasing the amount of power delivered to the output of the power converter in response to such error signal.
Conventional power converters typically generate an error signal by sensing the output voltage as an analog value, deriving the difference between the sensed output voltage and the reference voltage as an analog value and amplifying it. Conventional power converters may also use an analog-to-digital converter (A/D converter) for the error signal depending upon the control scheme. Other conventional power converters may use analog error amplifiers to generate the error signal. Conventional power converters cannot generate the error signals in real time at the operating frequency of the power converter, although real time detection of certain events in the power converters and real time generation of error signals would significantly improve the performance of power converters.
Therefore, there is a need for a power converter that does not require an A/D converter or analog error amplifier in generating a digital error signal. There is also a need for a power converter that can generate digital error signals in real time at the switching frequency of the switch in the power converter. There is also a need for a power converter that does not require external circuitry for generation of the digital error signals.